As agent Michael Glennon of the FBI Human Trafficking Task force rushed into the hotel room in suburban Detroit, all he could hear were the screams of protest from the petite blonde being detained by one of his team members. The undercover officer had arranged a date with the young woman advertised as “Lil’ Barbie,” who investigators feared was underage. This was part of the Innocence Lost initiative, a nationwide sting operation aimed at identifying and rescuing children from pimps and predators.

"Lil' Barbie" and her pimp were both taken into custody as part of the Federal Bureau of Investigation's ongoing effort to fight trafficking of children. Together with local law enforcement agencies like the Michigan State Police, the FBI is dedicated to stemming the tide of children who are sold for sex by criminals.

“Those are our main targets, the ones that have the 14-, 15-, 16-year-old kids that are walking the street, that are out there on the Internet,” said Glennon.

Despite the city’s well-documented economic woes, the selling of sex in Detroit is still a thriving business. For this reason, the FBI created human trafficking task forces in 26 major cities. The task force brings together the federal, state and local law enforcement, including victim specialists who pull underage children off the streets and out of the hands of predators.

For "Lil’ Barbie" Tina — like a majority of those who end up working in the sex trade — a life of sexual servitude in Detroit began in childhood at a very young age.

At age five, Tina came home from kindergarten and her mother told her to go into the bedroom, where two men raped her. Her mother, who was addicted to drugs, had sold her to the neighborhood men to feed her habit. "I didn't even understand the difference between boys and girls at that point." After surviving decades of being beaten, raped, abused and exploited by pimps and predators, Tina struggled to find a way out of prostitution.

"I've been stabbed in the face with a screwdriver, burned on my back with an iron and thrown out of a car on the highway. All, because I didn't want to work in this life anymore," shared Tina.

A friend referred her to Detroit's Alternatives for Girls, one of the few non-profit organizations in the country that provides long term therapy and counseling to help get young women out of cycle of violence of being prostituted. "They saved my life," says a grateful Tina, who currently works at Alternative for Girls as a mentor.

Within a four-hour span on the first day of the operation, the Detroit Task Force recovered four underage girls, made some 30 arrests and initiated over a dozen cases in three long days.

“It feels like progress, but it feels like there’s so much more out there that we just don’t know,” said Glennon. In explaining why, at the end of the day, many victims like Tina decide to return to the street and ultimately their pimps, he says, “You realize this may be the only thing that they have. This may be the only family that’s there for them. This may be the only way that they feel they can survive.”

Operations like these are costly. Beyond the array of manpower needed to run such an operation safely, Michigan State Police Sergeant Ed Price, who partners with the federal task force, estimates it will take an additional two weeks just to process all of the information that they have gathered over the weekend. But the hard work and long hours will eventually pay off by evolving into state and federal prosecutions.

“It’s very worth it. They guys and girls that do this job, we do it for the kids. We do it because it needs to be done.”

Watch 'Sex Slaves: Motor City' on MSNBC on Sunday, May 15 at 10 p.m. EST. For more information on how to help victims of trafficking in Detroit contact Alterntaivesforgirls.org.

Video: Sex slaves: A growing industry in the U.S.

Closed captioning of: Sex slaves: A growing industry in the U.S.

>>>human trafficking
is becoming
big business
in this country. more criminal syndicates are getting into the business of selling
young women
, trapping them in an endless cycle of abuse and violence. we'll talk to one of the women who survived in a moment. first in
2003
the
fbi
launched an initiative dubbed "innocence lost." we went to
detroit
to ride along during operation cross-country. on the streets of
detroit
and throughout michigan,
hard times
are leading to hard choices. for a growing number of
young women
, caught up in the underground
sex trade
.

>>domestic trafficking in the
state of michigan
is a huge problem.

>>coming in.

>>we have seen cases involving 12 and 13-year-olds in small towns. we have seen cases involving young girls in the
big cities
here. they are
modern day
slaves on the streets all around us.

>> reporter: investigators with the
fbi
's
human traffickingtask force
are on the streets of
detroit
metro conducting undercover
sting operations
. one
young woman
in particular has captured the team's attention. she goes by the name lil
barbie
and appears quite young.

>>i thought a half hour for $150.

>> reporter: within an hour, lil
barbie
calls back and makes a date with under cover officer richard sanchez at a local motel. officers must
stay close
enough to protect sanchez without blowing his cover.

>> reporter: like thousands before her, heather's path to prostitution began with desperate circumstances.

>>i wanted to go to school. i had nowhere to live. so i was stuck walking the street. doing this life. i was trapped out there basically.

>> reporter: officers will now try to offer the teen a different way out.

>>if you want out, if you want us to get you in a shelter, get you in a program to get you out of this life, we can.

>>when you take a female prostitute at the time of her arrest it's easy to come up with that understanding. like why are you doing this? to not be sympathetic. you knew what you were getting into. however when you get to know them, we find out their
life story
and you realize this may be the only way they feel they can survive.

>> reporter: agent michael glenon ran the
detroithuman traffickingtask force
until recently. tina is a survivor. she was trafficked on the streets of
detroit
starting at the age of 5. good morning to you both.

>>good morning.

>>as we see in the case of lil
barbie
she told you she had been beaten by her pimp just moments before you arrived. for people who think the girls are making a choice to do this, there is a cycle of abuse and violence that usually goes with this, right?

>>there is. it starts early.

>>mm-hmm.

>>what we have seen over a period of time is you take an individual, maybe from a broken home or from anywhere actually. you know, these exploiters, pimps, go in and they shower them with love, give them everything they have wanted, missed in life and over a period of time that's turned into manipulation. it's turned into fear. it entraps them, if you will. it debilitates them from going anywhere, doing anything else.

>>these girls, it is a cycle of violence and they often become victims of abuse. they endure many scars from their battles. the question is why don't they leave their pimps? why don't they run into the arms of the
fbi
?

>>as i just stated it's a difficult situation because what you've got is over a period of time this is what they have come to know as their family structure.

>>it's all they have.

>>it is. all the more reason why these
task forces
are so important.

>>we are seeing more of them across the country because it's becoming a real problem.

>>we are. specifically in
detroit
here, we partnered up with the
state police
, the local and county officials. and they have done a phenomenal job. really laying the foundation of really rescuing all the victims out there.

>>tina, you became a victim at the age of 5. your own mother sold you to some neighborhood men. you have endured a horrible life, as we hear your story in this series as well. tell me about some of the battle wounds, the scars that you have from trying to escape this.

>>i have been stabbed in my chest from trying to get away. i have been stabbed in my face with a screwdriver. i have been burned with irons. told i was going to have to drink gasoline if i tried to get away. the only thing you can do is stay until you find someone you can trust to get you out.

>>you found a great program called alternative for girl which we feature on the series as well.